title: A controlled trial of lambda-cyhalothrin-impregnated bed nets and/or dapsone/pyrimethamine for malaria control in Sierra Leone.
abstract: A randomized controlled trial investigated the impact of community-wide use of mosquito nets impregnated with lambda-cyhalothrin alone or with dapsone/pyrimethamine (d/p) prophylaxis on clinical malaria due to perennially transmitted Plasmodium falciparum in children in the Bo district of Sierra Leone. The 17 study communities were pair-matched and randomly allocated to receive treated mosquito nets or no nets and the children (age range = 3 months-6 years) in each community were randomly allocated to receive d/p or placebo individually every two weeks. This resulted in each of the approximately 2,000 children recruited being in one of four study groups (impregnated mosquito nets and d/p prophylaxis, impregnated mosquito nets, d/p prophylaxis, and controls). The intervention phase of the study lasted 12 months. A total of 1,800 children attended more than 25% of the 48 total weekly morbidity surveillance surveys and were included in the analysis. The effects of the exclusive use of either treated mosquito nets or d/p prophylaxis on protection against clinical malaria due to P. falciparum was significantly similar (49% and 42%, respectively), while in combination this protective efficacy was significantly increased to 72% (95% confidence interval = 67-76%). Children in the control group had an average of 1.3 clinical malaria episodes per child annually compared with 0.65 episodes or 0.78 episodes for those using treated mosquito nets and d/p, respectively. Children using both treated mosquito nets and d/p prophylaxis had an average of 0.37 episodes per child. The interventions significantly reduced spleen rates and increased hematocrit values, and reduced the duration of episodes of clinical malaria.
authors.affiliation: Department of Epidemiology and Population Sciences, London School of Hygiene and Tropical Medicine, United Kingdom.
authors.forename: N T
authors.initials: NT
authors.lastname: Marbiah
authors.forename: E
authors.initials: E
authors.lastname: Petersen
authors.forename: K
authors.initials: K
authors.lastname: David
authors.forename: E
authors.initials: E
authors.lastname: Magbity
authors.forename: J
authors.initials: J
authors.lastname: Lines
authors.forename: D J
authors.initials: DJ
authors.lastname: Bradley
mesh_terms: D000890:Anti-Infective Agents / Q000008:administration & dosage / Q000627:therapeutic use*; D001512:Bedding and Linens; D002648:Child; D002675:Child, Preschool; D003622:Dapsone / Q000008:administration & dosage / Q000627:therapeutic use*; D006801:Humans; D007223:Infant; D007306:Insecticides / Q000494:pharmacology*; D016778:Malaria, Falciparum / Q000175:diagnosis / Q000188:drug therapy* / Q000517:prevention & control*; D009032:Mosquito Control / Q000379:methods; D009570:Nitriles; D011722:Pyrethrins / Q000494:pharmacology*; D012008:Recurrence; D012807:Sierra Leone; D013154:Spleen / Q000469:parasitology
chemical_list: D000890:Anti-Infective Agents; D007306:Insecticides; D009570:Nitriles; D011722:Pyrethrins; D003622:Dapsone; C037304:cyhalothrin